This invention relates to devices for improving tension on auto seat belts to retain a child seat placed thereon.
It is a common practice to employ the automobile safety seat belts to secure the child seat in the automobile. The child seat manufacturer provides instructions to the consumer as to how to safely attach the child seat to the automobile, using the automobile safety seat belts. However, due to various configurations of the automobile safety seat belt systems, the sometime complex routing of the webbing of the automobile safety seat belt in the automobile and the sometimes complex path that the webbing passes around the child seat, access slack can remain in the automobile safety seat belt system which cannot be removed. This access slack in the safety seat belt system allows the child seat to excessively move relative to the automobile seat during an accident from it pre-accident position, thus exposing the child occupant to a greater risk of severe injury or even death. Unless otherwise mentioned, the phrase xe2x80x9cseat beltxe2x80x9d will refer to the auto or vehicle seat belt previously mounted in an auto or other vehicle (such as a seat on an airplane or boat) to restrain movement of a person sitting in that seat.
The prior art include a wide variety of belt tensioning devices. U.S. Pat. No. 6,092,869 describes a open U-shaped metal piece that receives the side of a seat belt so that the metal piece is rotated by a twisting motion on an arm extended from one of the U-ends of the metal piece. There is somewhat of a disadvantage in this device in that force from rotation of that arm is not well translated to the belt tightening rotation motion required for desired levels of belt tension.
U.S. Pat. No. 4,604,773 uses an open end dowel piece secured on both sides of the engaged belt in a support frame. In order to insert the dowel piece the hex opening and the hex ratchet on the opposite side must be perfectly aligned, this can be difficult to accomplish in places where accessibility is limited. The same, difficulty applies to the removal of the dowel piece where both sides of the hex opening must be perfectly aligned, as well.
U.S. Pat. Nos. 6,047,451 and 6,105,211 uses a center opening in a partially slotted rod to receive a seat belt to be wound around it. This center opening is difficult to engage the seat belt if it is narrow enough to be safe in retaining a highly tightened belt and potentially dangerous if wide enough to permit easy insertion of the seat belt. It is clear to the skilled person if the center opening to the slotted portion is great enough, the belt will simply slip free of the slotted portion in a sudden tightening of the belt as in an auto accident, resulting is a relatively un-tensioned belt and possibly increasing the harm to the child seat occupant. Another disadvantage is that in order to remove the device the seat belt must be first completely unwound from the partially slotted rod, the seat belt has to be released from its retaining slotted portion of the rod and only then it may be removed.
U.S. Pat. No. 2,642,639 displays once again the prior art concern that a belt tensioning device should be secured on both sides of the belt for effective securement of the tensioning device.
U.S. Pat. No. 5,426,827 uses a non-ratcheting device for belt tensioning as in U.S. Pat. No. 6,092,869.
There is a need for a device that overcomes the limitations of the prior art so that the user can have the benefit of an open-end slotted device with mechanical advantage of the devices that are supported on both sides of a seat belt.
A tensioning device used to improve the retention of a child seat after its installation in an auto seat using its installed seat belts. After the child seat is placed on the auto seat and the seat belt is engaged about the child seat in a desired manner, the device increases tension in the seat belt to improve retention of the child seat. The device uses a rotatable spool around which the auto seat belt is wrapped. Lever means connect with rotating and locking means, which in turn connect to the rotatable spool to wind the spool in a direction such that would result in effectively shortening of the automobile seat belt. A rotation preventing arm, similar in function to the rotation preventing arm of U.S. Pat. No. 6,092,869, extends from the device frame so that it does not rotate with either the spool or the lever means but is integral with the rotating and locking means in a manner that causes the spool to be prevented from rotating against the urging direction of the seat belt wound around the spool. The rotation preventing arm (or securing arm) prevents the spool from unwinding thus releasing the webbing.
The device can easily be removed from the seat belt by releasing the tension on the seat belt and sliding it in a direction perpendicular AND AWAY FROM to the seat belt.
The purpose of the present invention is to provide the user with a device that would allow him to remove the access slack from the automobile safety seat belt system and to increase and maintain the tension on the automobile safety seat belt. The reduced slack and increase belt tension will result in a more secured child seat installation, reducing its movement relative to the automobile seat during an accident, and thus reducing the risk of severe injury or even death to the child occupant.